Will the varicella vaccine lead to a significant reduction in the incidence of shingles (herpes zoster) in future generations? Since the vaccine does not actually cause the virus to go dormant in the spinal cord, can/will these patients ever get shingles?
—TISH ARTHUR, PA-C, Florence, Ky.
The varicella “chickenpox” vaccine (Varivax) is a live attenuated vaccine that was licensed in 1995 and is effective in preventing primary infection with wild-type varicella-zoster virus (VZV). Whether varicella vaccination has an effect on the incidence of herpes zoster in individuals who never received the Varivax varicella vaccine is unclear. An initial rise in the incidence of herpes zoster was predicted secondary to the anticipated fall in varicella incidence, and early studies supported this hypothesis. However, a more recent investigation demonstrated that the incidence of shingles has been stable as the incidence of chickenpox declined between 1992 and 2002.
Herpes zoster represents clinical re-infection in persons who previously had a primary varicella infection. Elevated cellular immune response (reflected by increased VZV antibodies) confers protection from clinical re-infection (herpes zoster) in people who have previously had varicella infection. Yet age younger than 1 year, mild varicella infection (without an adequate immune response), and genetics are risk factors for the development of herpes zoster—even in immunocompetent individuals who had a prior episode of chickenpox. However, herpes zoster vaccine (Zostavax) is not recommended for people of any age who previously received varicella vaccine. Hence continued surveillance is warranted to observe whether immunocompetent individuals who receive Varivax subsequently develop shingles. For more information, see J Drugs Dermatol. 2008;7:1173-1176 and J Am Acad Dermatol. 2008;58:361-370).
—Philip R. Cohen, MD (129-9)